Dear MPI-Forum, I have some difficulties to interpret the naming schemes in section 19.1.5 (MPI 4.0 standard): Consider two routines (e.g. MPI_Send, MPI_Recv) in the same Fortran support method (e.g. 'use mpi_f08'), that both take a choice buffer argument. Does the Standard (a) allow to implement one routine with naming scheme 1A (MPI_Send_f08) and the other with scheme 1B (MPI_Recv_f08ts), (b) demand that 1B (_f08ts) is used either for all routines with choice buffer arguments or none, (c) something else entirely? My interpretation of this paragraph(p.798, 5-7)     The mpi and mpi_f08 modules and the mpif.h include file will each correspond to     exactly one implementation scheme from Table 19.1. However, the MPI library may contain     multiple implementation schemes from Table 19.1. depends whether there are only two distinct naming schemes 1 and 2(each with two sub-options A and B) or  four  distinct naming schemes 1A, 1B, 2A and 2B. The first would imply (a), the second would imply (b). On the other hand, p.798, line 1-3:     To set MPI_SUBARRAYS_SUPPORTED to .TRUE. within a Fortran support method,     it is required that all nonblocking and split-collective routines with buffer arguments are     implemented according to 1B and 2B implies option (a). Best, Gregor